Voltage regulation control method and system for new energy station

Abstract

The invention provides a voltage regulation control method and system for a new energy station. The voltage regulation control method for the new energy station comprises the following steps: calculating a corrected voltage drop value according to the voltage of a high-voltage bus prime mover side of a grid-connected point, a first voltage difference compensation amount and a second voltage difference compensation amount; calculating a system equivalent impedance value according to the corrected voltage drop value and the first electrical information value and the second electrical information value of the reactive voltage state of the generator set of the grid-connected point; according to the first electrical information value, a regulation voltage target instruction value and the system equivalent impedance value, determining a reactive target regulation variable; and according to the reactive target adjusting quantity, controlling the reactive equipment of the station to carry out adjustment, wherein the second voltage difference compensation amount is positively correlated with the phase angle difference and the amplitude difference between the voltage of the high-voltage bus generator set side and the voltage of the prime motor side. According to the embodiment of the invention, the reactive power regulation error can be reduced, and the regulation period can be shortened.

Description

Technical Field

[0001] The present application relates to the technical field of power systems, and in particular to a voltage regulation control method and system for a new energy station. Background Art

[0002] With the increase in installed capacity of new energy power plants such as wind farms and photovoltaic power plants, the safe and stable operation of grid-connected new energy power plants and the power grids in the regions where they are connected has received increasing attention. At present, the automatic voltage control systems of domestic new energy power plants all adopt the voltage regulation mode. The connection of large-scale wind power and photovoltaic power plants to the grid will cause serious voltage fluctuations in the power grid, especially the voltage fluctuations at the access points. In the case of severe fluctuations in the system bus voltage, the traditional automatic voltage control and regulation system has a long regulation cycle and slow speed, which makes it difficult to meet the needs of rapid regulation of new energy power plants. Summary of the invention

[0003] The present application provides a voltage regulation control method and system for a new energy station, which is used to solve the problems of low precision and long regulation cycle in the traditional automatic voltage control regulation method. The following introduces various aspects involved in the present application.

[0004] In a first aspect, the present application provides a voltage regulation control method for a new energy station, including: calculating a corrected voltage drop value according to the voltage on the prime mover side of the high-voltage busbar at the grid-connected point, a first pressure difference compensation amount, and a second pressure difference compensation amount; calculating a system equivalent impedance value according to the corrected voltage drop value, a first electrical information value and a second electrical information value of the reactive voltage state of the generator set at the grid-connected point; determining a reactive target regulation amount according to the first electrical information value, a voltage regulation target instruction value, and the system equivalent impedance value; and controlling the reactive target regulation amount according to the reactive target regulation amount. The reactive equipment of the station is adjusted; wherein the first pressure difference compensation amount is a reactive correction amount, and the first pressure difference compensation amount is positively correlated with the reactive power on the high-voltage bus generator set side of the grid connection point and the system equivalent impedance value; the second pressure difference compensation amount is positively correlated with the power angle and the first amplitude difference, the power angle is the phase angle difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side, and the first amplitude difference is the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side corresponding to the power angle.

[0005] In the second aspect, the present application provides a voltage regulation control system for a new energy station, including: a first calculation module, used to calculate a corrected voltage drop value according to the voltage on the prime mover side of the high-voltage busbar at the grid connection point, a first pressure difference compensation amount and a second pressure difference compensation amount; a second calculation module, used to calculate a system equivalent impedance value according to the corrected voltage drop value, a first electrical information value and a second electrical information value of the reactive voltage state of the generator set at the grid connection point; a determination module, used to determine a reactive target regulation amount according to the first electrical information value, a voltage regulation target instruction value and the system equivalent impedance value; a regulation module, used to According to the reactive target adjustment amount, the reactive equipment of the station is controlled to be adjusted; wherein, the first pressure difference compensation amount is a reactive correction amount, and the first pressure difference compensation amount is positively correlated with the reactive power on the high-voltage bus generator set side of the grid connection point and the system equivalent impedance value; the second pressure difference compensation amount is positively correlated with the power angle and the first amplitude difference, the power angle is the phase angle difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side, and the first amplitude difference is the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side corresponding to the power angle.

[0006] In a third aspect, the present application provides a voltage regulation control system for a new energy station, comprising: a memory for storing code; a processor connected to the memory, for executing the code stored in the memory, so that the voltage regulation control system performs the voltage regulation control method described in the first aspect.

[0007] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method described in the first aspect can be implemented.

[0008] In a fifth aspect, the present application provides a computer program product, which, when executed on an electronic device, enables the electronic device to implement the method described in the first aspect.

[0009] In the embodiment of the present application, the corrected voltage drop value is calculated based on the voltage on the prime mover side of the high-voltage bus at the grid connection point, the first pressure difference compensation amount and the second pressure difference compensation amount. The second pressure difference compensation amount is positively correlated with the phase difference between the voltage on the high-voltage bus generator set side and the voltage on the prime mover side, and the second pressure difference compensation amount is positively correlated with the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the prime mover side. Compared with the traditional AVC voltage regulation method, the embodiment of the present application does not ignore the amplitude difference caused by the voltage fluctuation on both sides of the system high-voltage bus, and uses active power correction to calculate the voltage regulation formula, which has a higher calculation accuracy for the system equivalent impedance value and the AVC voltage regulation formula. The embodiment of the present application helps to reduce the reactive regulation error, more accurately regulate the AVC voltage, shorten the regulation cycle, improve the stability of the system, and help solve the problems of large fluctuations in power generation and slow response speed in new energy stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in describing the embodiments of the present application are briefly introduced below.

[0011] Figure 1 It is a schematic diagram of an AVC voltage regulation system provided by the related technology.

[0012] Figure 2 yes Figure 1 Schematic diagram of the regulation process of the AVC voltage regulation system.

[0013] Figure 3 It is a schematic diagram of a single-machine-infinite system.

[0014] Figure 4 yes Figure 3 Schematic diagram of voltage fluctuation on both sides of the system high-voltage bus.

[0015] Figure 5 It is a flow chart of the voltage regulation control method for a new energy station provided in an embodiment of the present application.

[0016] Figure 6 It is a schematic diagram of the voltage fluctuation on both sides of the system high-voltage bus after correction provided in an embodiment of the present application.

[0017] Figure 7 yes Figure 3 A flowchart of a possible implementation of the method.

[0018] Figure 8 yes Figure 5 A flowchart of a possible implementation method of step S510 in FIG.

[0019] Fig. 9It is a schematic diagram of a voltage regulation control system of a new energy station provided in an embodiment of the present application.

[0020] Fig.10 yes Fig. 9 A schematic diagram of a possible implementation of a voltage regulation control system.

[0021] Fig.11 yes Fig.10 Schematic diagram of the adjustment process of the voltage regulation control system.

[0022] Fig.12 It is a schematic diagram of component units / partial component units of another voltage regulation control system of a new energy station provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The same or similar reference numerals are used in the drawings to represent the same or similar modules. It should be understood that the drawings are only schematic, and the protection scope of the present application is not limited thereto.

[0024] With the increase in installed capacity of renewable energy power plants such as wind farms and photovoltaic power plants, the safe and stable operation of grid-connected renewable energy power plants and the regional power grids they are connected to has received increasing attention. Voltage, as an important criterion for measuring power quality, has received more extensive attention. In order to avoid causing unstable bus voltage and suppress voltage fluctuations at the access point of renewable energy power plants, the system will perform reactive power repair through automatic voltage control (AVC) to ensure that the bus voltage is qualified.

[0025] In recent years, with the continuous access of new energy sources such as wind power and photovoltaic power to the power grid, the intermittency, randomness and uncontrollability brought about by the access have brought some new challenges to the operation of the power grid. The connection of large-scale wind power and photovoltaic power plants to the grid will cause serious voltage fluctuations in the power grid, especially at the access point.

[0026] At present, the AVC systems of domestic new energy power plants all adopt the voltage regulation mode. Figure 1 Schematic diagram of the AVC voltage regulation system provided by the related technology. Figure 1 As shown, in the traditional AVC voltage regulation system, the system impedance value X and the target voltage value U issued are used. set , the reactive power target adjustment quantity Q is calculated by the AVC voltage adjustment formula set The reactive power target adjustment amount is decomposed by calculation. Then, combined with various dead zone limits, the reactive power target adjustment amount Q for different units is determined. set(k) so that the reactive equipment can be adjusted. Where k is a positive integer between 1 and n. The reactive target adjustment amount is also called the reactive target amount, the reactive power target adjustment amount. In the entire system, the key to AVC regulation is to accurately calculate the system impedance value X and the reactive target adjustment amount Q. set , and then accurately sent to each unit for adjustment.

[0027] Specifically, Figure 2 As shown, in the traditional AVC voltage regulation system, the system impedance value X obtained by calculation and the regulation target voltage value U issued are set , calculate the reactive power target regulation quantity Q set , and then decide whether to start regulation by setting the dead zone threshold. The AVC voltage regulation system is generally a minute-level regulation device, with a cycle set to about 15 to 30 seconds. After the regulation system is turned on, the reactive target regulation command value Q of each reactive device is calculated. set (k) is sent to the reactive device to realize closed-loop regulation and control. Each reactive device can be regulated based on a static var generator (SVG) or a static var compensator (SVC). The actual reactive power of any reactive device is sampled in real time, and the measured reactive power value Q 实测AVC (k) Feedback to the control front end and the reactive power value Q AVC (k) is compared and the difference is gradually reduced. For example, the reactive power target adjustment command value Q of the generator set can be determined by proportional integral (PI) adjustment. set (k) and adjusting the target voltage value U set The actual AVC voltage regulation effect is manifested as the system bus voltage changes with the voltage target command value U set changes and maintain the system bus voltage converging within the preset dead zone range of the regulated voltage target command value.

[0028] From the above, the reactive power target regulation quantity Q is solved by traditional SVC set From the process, it can be seen that the SVC voltage regulation method sends the target voltage value U set , through U set And the system equivalent impedance value X to the reactive power target regulation Q set To solve.

[0029] However, the traditional SVC voltage regulation method has large errors, and the regulation cycle of the AVC substation in the renewable energy power field is long. When the grid-connected bus voltage fluctuates rapidly and frequently due to external reasons, the AVC system cannot adjust the fluctuations in a timely, accurate and rapid manner. There will be a phenomenon that the measured voltage fluctuates in the opposite direction before the previous cycle is regulated. At this time, voltage oscillation will occur, resulting in the inability of regulation to converge to the dead zone range of the voltage target command value, thereby affecting the safe operation of the entire power grid system.

[0030] It can be seen that when the system bus voltage fluctuates severely, the traditional SVC voltage regulation system has a long regulation cycle and slow speed, which makes it difficult to meet the needs of rapid regulation of new energy power fields.

[0031] Therefore, it is necessary to design a technical solution for station voltage regulation with high precision and fast regulation speed.

[0032] Based on this, the embodiment of the present application proposes a voltage regulation control method for a new energy station. In the process of proposing the technical solution of the voltage regulation control method for a new energy station of the present application, the embodiment of the present application first analyzes the calculation process of the traditional SVC voltage regulation method, and explores the links in the SVC voltage regulation process that can reduce the voltage regulation error.

[0033] The single-machine-infinite system ignores the complexity of the power system, making the analysis relatively simple, and the single-machine-infinite system can be used as the analysis and research object. Figure 3 It is a schematic diagram of a single machine-infinite system. Figure 3 As shown in the figure, the voltage, active power and reactive power on the generator side of the system busbar at the grid connection point are represented by U, P and Q respectively, and the voltage, active power and reactive power on the prime mover side of the system busbar at the grid connection point are represented by U s , P s , Q s The traditional SVC voltage regulation method adopts the calculation method of active voltage drop.

[0034] Figure 4 yes Figure 3 The voltage fluctuation diagram of the system high-voltage busbar on both sides can be expressed as follows: Figure 4 As shown. Among them, the power angle δ represents the phase difference of the voltage on both sides of the system high-voltage bus, that is, the phase angle of the voltage U on the generator side of the system bus and the voltage U on the prime mover side of the system bus. s δU represents the amplitude difference caused by the system bus voltage fluctuation, that is, the voltage U on the system bus generator side and the voltage U on the system bus prime mover side. sΔU represents the first pressure difference compensation on both sides of the system bus. The vector direction of ΔU is consistent with the vector direction of Us, and the vector direction of ΔU is perpendicular to the vector direction of δU.

[0035] The voltage difference on both sides of the system bus is shown in Equation 1:

[0036]

[0037] After substituting the numerical values, the sub-items of the voltage difference on both sides of the system bus, the first voltage difference compensation ΔU and δU can be calculated, as shown in Equation 2 and Equation 3:

[0038]

[0039] The voltage drop formula used is shown in Equation 4:

[0040] U=U s +ΔU Equation 4

[0041] It can be seen that in the conventional AVC voltage regulation method, the power angle δ generated during the voltage fluctuation on both sides of the system bus is negligible, and the amplitude difference caused by δU is also negligible. set In the process of solving, the amplitude difference caused by the voltage fluctuation on both sides of the system bus corresponding to δU is ignored. When the power angle δ deviation is too large, this method will affect the impedance evaluation calculation value X and the reactive power target adjustment value Q. set The calculation of will produce large errors, affecting the accuracy and response speed of the system to SVC voltage regulation, which will lead to slow regulation speed and long regulation cycle of the SVC voltage regulation system.

[0042] Therefore, the embodiment of the present application proposes an AVC voltage regulation method with active power correction. A new algorithm with active power correction is used to replace the original system equivalent impedance X and reactive power regulation target value Q. set When the bus voltage fluctuates greatly, the accuracy of reactive power regulation target value calculation can be improved, the accuracy and timeliness of AVC voltage regulation can be ensured, the reactive power regulation cycle can be shortened, and the output control of reactive equipment can be made more accurate.

[0043] Combine the following Figure 5 The voltage regulation control method of the new energy station in the embodiment of the present application is described in detail. Figure 5 As shown, the voltage regulation control method of the new energy station in the embodiment of the present application may mainly include steps S510 to S540, and these steps are described in detail below.

[0044] It should be pointed out that the size of the serial numbers of the steps in the embodiments of the present application does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0045] In step 510, a corrected voltage drop value is calculated based on the voltage on the prime mover side of the high-voltage bus at the grid connection point, the first pressure difference compensation value, and the second pressure difference compensation value.

[0046] Among them, the first pressure difference compensation amount is positively correlated with the reactive power and system equivalent impedance value of the high-voltage bus generator set side of the grid connection point. The second pressure difference compensation amount is positively correlated with the power angle and the first amplitude difference. Among them, the power angle is the phase angle difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side, and the first amplitude difference is the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side corresponding to the power angle.

[0047] Likewise Figure 3 Take a single-machine-infinite system as an example. Figure 6 is a schematic diagram of the voltage fluctuation on both sides of the system high-voltage bus after correction provided by the embodiment of the present application. Specifically, Figure 6 As shown, the vector direction of the first amplitude difference (δU) is perpendicular to the vector direction of the voltage Us on the prime mover side of the high-voltage bus; δU is approximately equal to the voltage between U and U s The extended line is a vector perpendicular to the bisector of the power angle δ. The value of sin(δ) can be calculated, and sin(δ / 2) can be used to represent sin(δ) by the approximate equality method. The calculation process is shown in Equation 5 and Equation 6.

[0048]

[0049] Similarly, the solution formula for the second pressure difference compensation amount (ΔU′) can be obtained in an approximately equal manner, as shown in Formula 7:

[0050]

[0051] It can be seen that the second pressure difference compensation amount (ΔU′) is positively correlated with the power angle δ and the first amplitude difference (δU).

[0052] The larger the power angle δ, the larger the amplitude difference δU between the voltage on the high-voltage bus generator side and the voltage on the prime mover side, and the larger the value of the second voltage difference compensation amount. Therefore, in the case of severe fluctuations in the system bus voltage, especially when the power angle δ is large, the amplitude difference caused by δU should not be ignored.

[0053] Then the corrected voltage drop value is obtained, as shown in formula 8:

[0054] U 修 =Us +ΔU+ΔU′ Formula 8

[0055] According to the calculated values ​​of equations 2 and 3, substituting them into equation 8, the corrected voltage drop value can be obtained, as shown in equation 9:

[0056]

[0057] In some implementations, the power angle δ is greater than the first angle threshold. The first angle threshold may be 25° or 30°. For example, in the case of severe bus voltage fluctuations, the power angle δ caused by voltage fluctuations on both sides of the bus may be greater than 30°. The amplitude difference caused by δU is not ignored, and the voltage drop value is calculated using the calculation method of formula 9, which helps to improve the calculation accuracy of the voltage drop value.

[0058] In some implementations, the rated voltage of the new energy station in the embodiment of the present application is greater than or equal to 110 kV, and the system equivalent impedance value is greater than 5 times the system resistance value. For the system model of high-voltage lines of 110 kV and above, the system equivalent impedance value X exceeds five times the resistance R, and the influence of the resistance R on the system can be ignored.

[0059] Right now The first pressure difference compensation amount ΔU is a reactive power correction amount. That is, the second pressure difference compensation amount is the active correction amount. It can be seen that the second pressure difference compensation amount is positively correlated with the square value of the active power on the high-voltage bus generator side and the square value of the system equivalent impedance value, and the second pressure difference compensation amount is negatively correlated with the cube of the voltage on the high-voltage bus generator side.

[0060] Then the corrected voltage drop value U of the system is obtained. 修 , as shown in formula 10:

[0061]

[0062] In the embodiment of the present application, by making an auxiliary line for the power angle δ, the corrected voltage drop value is recalculated. 修 Symmetrical about the bisector of the power angle δ, the error between the two is smaller. The second voltage difference compensation amount is an active power correction amount, so the method of the embodiment of the present application is also called an AVC voltage regulation method with active power correction. Using the calculation method with active power (Formula 10), the voltage drop value of the system is corrected and calculated, and a more accurate voltage drop value can be obtained.

[0063] In step S520, the system equivalent impedance value is calculated according to the corrected voltage drop value, the first electrical information value and the second electrical information value of the reactive voltage state of the generator set at the grid connection point.

[0064] The important process of AVC voltage regulation with work correction is: the calculation of impedance evaluation value X. Unlike conventional AVC voltage regulation, the amplitude deviation caused by δU is no longer ignored, so the impedance evaluation value calculated will be closer to the system impedance value. The calculation process is as follows.

[0065] Assuming that Us is stable, when the reactive voltage state of the generator set (G) changes from the initial state to the second state, the initial state is also called the first state, and the first electrical information value corresponding to the initial state is (U0, Q0, P0), where U 0、 P 0、 Q0 is the voltage, active power, and reactive power of the generator set in the initial state of outputting reactive voltage. The second electrical information value (U2, Q2, P2) corresponding to the second state, U 2、 P 2、 Q2 is the voltage, active power and reactive power of the second state in which the generator set outputs reactive voltage.

[0066] As an example, the electrical information values ​​of the grid connection point of the new energy station can be obtained through various sensors. The electrical information values ​​may include but are not limited to active power measurement values, voltage measurement values ​​and reactive power measurement values, and these measurement values ​​can all be average values. As an example, the active power measurement value can be obtained by an instrument such as a power analyzer that is specifically used to measure parameters such as power, or it can be calculated by measuring voltage and current through current and voltage sensors. The reactive power measurement value can be obtained by measuring with a reactive meter, or by calculating the active power and apparent power. As an example, the above electrical information values ​​can all be obtained from telecontrol equipment.

[0067] After the system is regulated by AVC voltage with active power correction, the corrected voltage drop values ​​U0 and U2 are obtained, as shown in formula 11:

[0068]

[0069] The system equivalent impedance value X is derived by the calculation formula of U0 and U2, as shown in formula 12:

[0070]

[0071] By solving the quadratic equation of formula 12, the system equivalent impedance value X can be obtained, which takes a value greater than zero.

[0072] Since the amplitude difference caused by δU is taken into account, a more accurate evaluation value of the system equivalent impedance can be obtained by calculating and deriving the voltage regulation formula using active power correction.

[0073] In step S530, a reactive power target adjustment amount is determined according to the first electrical information value, the adjustment voltage target instruction value and the system equivalent impedance value.

[0074] Active power correction AVC voltage regulation is suitable for situations where voltage fluctuations are large. It takes into account the role of system active power and makes the calculated reactive power target regulation more accurate. After obtaining the corrected system equivalent impedance value X, the most important thing for the reactive power regulation of the system is the reactive power target regulation Q. set The calculation is the AVC voltage regulation calculation with active power correction. The reactive power target regulation is also called reactive power target regulation.

[0075] In the calculation process of this system, it is assumed that U s Stable, when the generator set (G) outputs the initial state of reactive voltage (U0, Q0, P0), it receives the voltage command and adjusts to U set The specific calculation process is as follows: the reactive state (U0, Q0, P0) output by the generator set and the received voltage regulation target command value U set Substituting into the voltage drop calculation formula (Equation 10), we get

[0076] Formula 13:

[0077]

[0078] By calculation, the reactive power target adjustment quantity Q can be obtained. set The size of is shown in Equation 14 and Equation 15:

[0079]

[0080] By re-analyzing and calculating the power angle deviation δ as an auxiliary line, the system voltage drop value, system equivalent impedance value X and AVC voltage regulation are calculated using a calculation method with power, and a more accurate reactive power target regulation amount is obtained.

[0081] In step S540, the reactive equipment of the station is controlled to be adjusted according to the reactive target adjustment amount.

[0082] The total reactive power target value is sent to each power generation unit and reactive equipment, and distributed according to the predetermined distribution strategy. The reactive power command distribution of the reactive compensation equipment can be average distribution, proportional distribution, similar margin distribution and optimized distribution, etc. This application does not limit the specific distribution method.

[0083] In the embodiment of the present application, the corrected voltage drop value is calculated based on the voltage on the prime mover side of the high-voltage bus at the grid connection point, the first pressure difference compensation amount and the second pressure difference compensation amount. The second pressure difference compensation amount is positively correlated with the phase difference between the voltage on the high-voltage bus generator set side and the voltage on the prime mover side, and the second pressure difference compensation amount is positively correlated with the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the prime mover side. Compared with the traditional AVC voltage regulation method, the embodiment of the present application does not ignore the amplitude difference caused by the voltage fluctuation on both sides of the system high-voltage bus, and uses active power correction to calculate the voltage regulation formula, which has a higher calculation accuracy for the system equivalent impedance value and the AVC voltage regulation formula. The embodiment of the present application helps to reduce the reactive regulation error, more accurately regulate the AVC voltage, shorten the regulation cycle, improve the stability of the system, and help solve the problems of large fluctuations in power generation and slow response speed in new energy stations.

[0084] The design principle of the voltage regulation control method of the embodiment of the present application is: when the system power angle δ deviates greatly, the amplitude difference caused by δU is processed by using a method with power calculation. The AVC voltage regulation method with power correction re-analyzes and calculates the power angle δ as an auxiliary line, and uses a method with power calculation to calculate the system voltage drop value, the system equivalent impedance value X and the AVC voltage regulation, so as to obtain a more accurate reactive power target regulation amount.

[0085] The method of the embodiment of the present application is further explained below in combination with some possible implementation methods of the present application.

[0086] Figure 7 yes Figure 5 A flow chart of a possible implementation of the method. Figure 7 As shown, the voltage regulation control method of the embodiment of the present application may mainly include steps S710 to S794, and these steps are described in detail below.

[0087] In step S710, the target value of the scheduling or the local target value is used, that is, the target voltage instruction value U is determined. set .

[0088] In step S720, start.

[0089] In step S730, it is determined whether the AVC function is enabled.

[0090] If the AVC function is enabled, the process proceeds to step S740 ; if the AVC function is not enabled, the process proceeds to step S750 .

[0091] In step S740, the operating condition data is updated and the configuration data is updated.

[0092] In step S750, the delay process is performed, and the process goes to step S720 again after the preset delay time is reached.

[0093] In step S760, topology identification is performed.

[0094] The main contents of topology identification include: identifying the operating status of the high-voltage side bus, identifying the operating status of the main transformer, identifying the operating status of the low-voltage side, identifying the operating status of the new energy management platform, and identifying that the SVG status is in normal state.

[0095] In step S770, the target voltage command value U is determined. set Whether to update.

[0096] Confirm the voltage adjustment target command value U set The target voltage is the latest one issued. If it has been updated, go to step S780; if it has not been updated, go to step S750.

[0097] In step S780, it is confirmed whether it is a locking adjustment.

[0098] Perform constraint condition calculation, and determine whether it is a lock adjustment according to the global lock mark and the booster station lock mark. If it is not a lock adjustment, proceed to step S790; if it is a lock adjustment, proceed to step S750.

[0099] In step S790, the reactive power target adjustment quantity Q with active power correction is calculated. set .

[0100] In step S791, reactive power is distributed according to a set distribution method.

[0101] According to the total reactive power target regulation amount and the set allocation method, each reactive power device is allocated its own reactive power regulation value.

[0102] In step S792, the reactive power regulation strategy is executed. Each reactive power device executes the corresponding reactive power regulation strategy.

[0103] In step S793, it is determined whether the voltage is within the voltage target command value U set within the set dead zone range.

[0104] If the system bus voltage is adjusted within the voltage target command value U set If it is within the set dead zone, the process proceeds to step S794; if it is not within the set dead zone, the process proceeds to step S750.

[0105] In step S794, the measured value is fed back. The measured voltage value is fed back to step S770.

[0106] Figure 8 yes Figure 5 A flowchart of a possible implementation of step S510 is shown in FIG. 1. In the AVC voltage regulation system, the AVC voltage regulation method with power correction mainly acts on the situation where the power angle δ caused by the voltage fluctuation on both sides of the bus is greater than the first angle threshold (such as 30°). Figure 8 As shown, step S510 may include steps S511 to S513, and these steps are described in detail below.

[0107] In step S511, the conventional AVC voltage regulation method (i.e., equation 2 and equation 3) is used to adjust the voltage U on the high-voltage bus generator side and the voltage U on the high-voltage bus prime mover side. s , solve the first pressure difference compensation amount ΔU.

[0108] In step S512, the corrected AVC voltage regulation method (i.e., Formula 7) of the embodiment of the present application is used to solve the second voltage difference compensation amount ΔU′ according to the voltage U, power angle δ and the first amplitude difference (δU) on the high-voltage bus generator side of the system.

[0109] In step S513, according to the voltage U s , the values ​​of the first pressure difference compensation amount ΔU and the second pressure difference compensation amount ΔU′, using the AVC voltage regulation method with correction (i.e., formula 10), the corrected voltage drop value U 修 .

[0110] In the embodiment of the present application, the corrected voltage drop value is calculated based on the voltage on the prime mover side of the high-voltage bus at the grid connection point, the first pressure difference compensation amount, and the second pressure difference compensation amount. The second pressure difference compensation amount is positively correlated with the power angle, and the second pressure difference compensation amount is positively correlated with the amplitude difference between the voltage on the high-voltage bus generator side and the voltage on the prime mover side. Compared with the traditional AVC voltage regulation method, the embodiment of the present application does not ignore the amplitude difference caused by the voltage fluctuation on both sides of the system high-voltage bus, and uses active power correction to calculate the voltage regulation formula, which has higher calculation accuracy for the system equivalent impedance value and the AVC voltage regulation formula. The embodiment of the present application helps to reduce reactive regulation errors, more accurately regulate the AVC voltage, shorten the regulation cycle, improve the stability of the system, and help solve the problems of large fluctuations in power generation and slow response speed in new energy stations.

[0111] Combination of the above Figure 1-Figure 8 The method embodiment of the present application is described in detail. Figures 9 to 12 The device embodiment of the present application is described in detail. It should be understood that the description of the device embodiment corresponds to the description of the method embodiment, so the parts not described in detail can refer to the previous method embodiment.

[0112] Fig. 9Schematic diagram of the voltage regulation control system of a new energy station provided in the embodiment of the present application. Fig. 9 As shown, the voltage regulation control system 900 of the new energy station includes: a first calculation module 910 , a second calculation module 920 , a determination module 930 and an adjustment module 940 .

[0113] The first calculation module 910 is used to calculate a corrected voltage drop value according to the voltage at the prime mover side of the high-voltage busbar at the grid connection point, the first pressure difference compensation amount, and the second pressure difference compensation amount.

[0114] Among them, the first pressure difference compensation amount is positively correlated with the reactive power and system equivalent impedance value of the high-voltage bus generator set side of the grid connection point. The second pressure difference compensation amount is positively correlated with the power angle and the first amplitude difference. The power angle is the phase angle difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side. The first amplitude difference is the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side corresponding to the power angle.

[0115] The second calculation module 920 is used to calculate the system equivalent impedance value according to the corrected voltage drop value, the first electrical information value and the second electrical information value of the reactive voltage state of the generator set at the grid connection point.

[0116] The determination module 930 is used to determine the reactive power target adjustment amount according to the first electrical information value, the adjustment voltage target instruction value and the system equivalent impedance value.

[0117] The regulation module 940 is used to control the reactive equipment of the station to perform regulation according to the reactive target regulation amount.

[0118] Optionally, the second pressure difference compensation amount is positively correlated with the square value of the active power on the high-voltage bus generator set side and the square value of the equivalent impedance value. The second pressure difference compensation amount is negatively correlated with the cube of the voltage on the high-voltage bus generator set side, and the second pressure difference compensation amount is an active correction amount. The first pressure difference compensation amount is a reactive correction amount.

[0119] Optionally, the rated voltage of the new energy station is greater than or equal to 110 kV, and the system equivalent impedance value is greater than 5 times the system resistance value.

[0120] Optionally, the power angle is greater than a first angle threshold.

[0121] Fig.10 yes Fig. 9 A schematic diagram of a possible implementation of a voltage regulation control system. Fig.10 As shown, the AVC voltage regulation with work correction is used to calculate the equivalent impedance value X of the system, and the system impedance value X and the adjusted target voltage value U are obtained. set , the reactive power adjustment target value Q is calculated by the AVC voltage regulation formula with active power correctionset Then, the reactive power target adjustment amount Q is calculated and then decomposed. Then, combined with various dead zone limits and safety constraints, the reactive power target adjustment amount Q for different units is determined. set (k) so that the reactive equipment can be adjusted. Where k is a positive integer between 1 and n.

[0122] Fig.11 yes Fig.10 Schematic diagram of the regulation process of the voltage regulation control system. Specifically, Fig.11 As shown in the figure, the system equivalent impedance value X obtained by calculation and the adjusted target voltage value U issued set , calculate the reactive power target regulation quantity Q set , and then decide whether to start the regulation by setting the dead zone threshold. After the regulation system is turned on, the reactive target regulation command value Q of each reactive device is calculated. set (k) is sent to the reactive equipment to realize closed-loop regulation and control. Each reactive equipment can be regulated based on a static VAR generator (SVG) or a static VAR compensator (SVC). The actual reactive power of any reactive equipment is sampled in real time, and the measured reactive power value Q is converted into 实测AVC (k) Feedback to the control front end and the reactive power value Q AVC (k) is compared and the difference is gradually reduced. For example, the reactive power target adjustment command value Q of the generator set can be adjusted by proportional integral (PI) set (k) and adjusting the target voltage value U set . Make the system bus voltage follow the target voltage command value U set and maintains the system bus voltage converging within the preset dead zone range of the target voltage command value.

[0123] In the embodiment of the present application, when the system voltage fluctuates greatly, reactive power regulation of the system is performed with a more precise regulation target value, which can reduce the system regulation cycle and improve system stability.

[0124] Fig.12 Schematic diagram of component units / partial component units of another voltage regulation control system of a new energy station provided in an embodiment of the present application. Fig.12 As shown, the voltage regulation control system 1200 of the new energy station may include: a memory 1210 and at least one processor 1220.

[0125] The memory 1210 is used to store codes or computer programs.

[0126] The processor 1220 is connected to the memory 1210 and is used to execute the code or computer program stored in the memory 1210 to control the management device 1100 of the power grid fault report of the information security system to execute any of the methods described above.

[0127] Exemplarily, the computer program may be divided into one or more modules / units, one or more modules / units are stored in the memory 1210 and executed by the processor 1220 to complete the present application.

[0128] Those skilled in the art will understand that Fig.12 This is only an example of the voltage regulation control system 1200 of the new energy station, and does not constitute a limitation on the voltage regulation control system of the new energy station. It may include more or fewer components than shown in the figure, or combine some components, or different components.

[0129] The processor 1220 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor, or the processor may be any conventional processor, etc.

[0130] The voltage regulation control system 1200 of the new energy station provided in this embodiment can execute the above method embodiment, and its implementation principle and technical effect are similar, which will not be repeated here.

[0131] An embodiment of the present application further provides a non-volatile computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments can be implemented.

[0132] An embodiment of the present application provides a computer program product. When the computer program product runs on an electronic device, the electronic device can implement the steps in the above-mentioned method embodiments when executing the computer program product.

[0133] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present application implements all or part of the processes in the above method embodiments, which can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above method embodiments can be implemented. Among them, the computer program includes computer program code, which can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may at least include: any entity or device that can carry the computer program code to the camera / electronic device, recording medium, computer memory, read-only memory (ROM), random access memory (RAM), read-only compact disc (CD-ROM), magnetic tape, floppy disk and optical data storage device. The computer-readable storage medium mentioned in the present application can be a non-volatile storage medium, in other words, it can be a non-transient storage medium.

[0134] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0135] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0136] In the embodiments provided in the present application, it should be understood that the disclosed devices / equipment and methods can be implemented in other ways. For example, the device / equipment embodiments described above are only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0137] It should be understood that when used in the present specification and the appended claims, the term "comprising" indicates the presence of described features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0138] It should also be understood that the term “and / or” used in the specification and appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0139] As used in the specification and appended claims of this application, the term "if" can be interpreted as "when" or "uponce" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrase "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "uponce it is determined" or "in response to determining" or "uponce [described condition or event] is detected" or "in response to detecting [described condition or event]", depending on the context.

[0140] In addition, in the description of the present application specification and the appended claims, the terms "first", "second", etc. are only used to distinguish the descriptions and cannot be understood as indicating or implying relative importance.

[0141] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A voltage regulation control method for a new energy station, characterized in that: include: Calculate the corrected voltage drop value according to the voltage on the prime mover side of the high-voltage busbar at the grid connection point, the first pressure difference compensation amount and the second pressure difference compensation amount; Calculating a system equivalent impedance value according to the corrected voltage drop value, the first electrical information value and the second electrical information value of the reactive voltage state of the generator set at the grid connection point; Determining a reactive power target adjustment amount according to the first electrical information value, the adjustment voltage target instruction value and the system equivalent impedance value; According to the reactive power target adjustment amount, controlling the reactive power equipment of the station to adjust; Among them, the first pressure difference compensation amount is a reactive correction amount, and the first pressure difference compensation amount is positively correlated with the reactive power on the high-voltage bus generator set side of the grid-connected point and the system equivalent impedance value; the second pressure difference compensation amount is positively correlated with the power angle and the first amplitude difference, the power angle is the phase angle difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side, and the first amplitude difference is the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side corresponding to the power angle.

2. The voltage regulation control method according to claim 1, characterized in that: The second pressure difference compensation amount is positively correlated with the square value of the active power on the high-voltage bus generator set side and the square value of the system equivalent impedance value, and the second pressure difference compensation amount is negatively correlated with the cube of the voltage on the high-voltage bus generator set side. The second pressure difference compensation amount is an active correction amount.

3. The voltage regulation control method according to claim 2, characterized in that: The corrected voltage drop value U 修 It is expressed as: Among them, U, P, Q are the voltage, active power, and reactive power on the high-voltage bus generator side, respectively; Us is the voltage on the high-voltage bus prime mover side; and X is the equivalent impedance value of the system.

4. The voltage regulation control method according to claim 3, characterized in that: The first electrical information value includes the voltage, active power, and reactive power of the initial state of the reactive voltage output by the generator set, and the reactive target adjustment value Q set It is expressed as: Among them, U0, P0, Q0 are the voltage, active power, and reactive power of the generator set in the initial state of outputting reactive voltage, U set is the target command value of the regulated voltage.

5. The voltage regulation control method according to any one of claims 1 to 4, characterized in that: The rated voltage of the new energy station is greater than or equal to 110 kV, and the system equivalent impedance value is greater than 5 times the system resistance value.

6. The voltage regulation control method according to any one of claims 1 to 4, characterized in that: The power angle is greater than a first angle threshold.

7. A voltage regulation control system for a new energy station, characterized in that: include: A first calculation module is used to calculate a corrected voltage drop value according to the voltage on the prime mover side of the high-voltage busbar at the grid connection point, the first pressure difference compensation amount, and the second pressure difference compensation amount; A second calculation module is used to calculate the system equivalent impedance value according to the corrected voltage drop value, the first electrical information value and the second electrical information value of the reactive voltage state of the generator set at the grid connection point; A determination module, configured to determine a reactive power target adjustment amount according to the first electrical information value, the adjustment voltage target instruction value and the system equivalent impedance value; A regulating module, used for controlling the reactive equipment of the station to perform regulation according to the reactive target regulation amount; Among them, the first pressure difference compensation amount is a reactive correction amount, and the first pressure difference compensation amount is positively correlated with the reactive power on the high-voltage bus generator set side of the grid-connected point and the system equivalent impedance value; the second pressure difference compensation amount is positively correlated with the power angle and the first amplitude difference, the power angle is the phase angle difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side, and the first amplitude difference is the amplitude difference between the voltage on the high-voltage bus generator set side and the voltage on the high-voltage bus prime mover side corresponding to the power angle.

8. The voltage regulation control system according to claim 7, characterized in that: The second pressure difference compensation amount is positively correlated with the square value of the active power on the high-voltage bus generator set side and the square value of the system equivalent impedance value, and the second pressure difference compensation amount is negatively correlated with the cube of the voltage on the high-voltage bus generator set side. The second pressure difference compensation amount is an active correction amount.

9. A voltage regulation control system for a new energy station, characterized in that: include: A memory for storing codes; A processor is connected to the memory and is used to execute the code stored in the memory so that the voltage regulation control system is a voltage regulation control method as described in any one of claims 1-6.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed, the computer program is used to implement the voltage regulation control method according to any one of claims 1 to 6.

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